Device for controlling the flow in a pipe system

ABSTRACT

In an eddy current brake for controlling quantitative flow in a water line and with a brake housing in the shape of lying frustum of a cone with an outlet opening in the narrow end and an inlet opening downwardly on the large end face there is disposed a guide vane opposite the inlet opening within the housing, said guide vane being rotatable about the axis of the housing by means of an exterior adjustment lever between a position in which it closes the inlet, and a position in which it is disposed completely outside the inlet region and thus allows free flow. In intermediate positions the guide vane deflects the in flowing stream of water toward the frusto-conical wall so that the water, when the pressure head exceeds a certain valve, is caused to rotate about the axis of the housing to produce the desired brake effect. This effect can be varied by adjustment of the guide vane. Its deflecting effect permits the inlet spout and outlet spout of the brake housing to be disposed in elongation of each other.

The invention relates to a device for controlling the flow in a pipesystem, such as a sewerage system, comprising a housing which isprovided with a curved side wall and forms a vortex chamber, and whichhas an inlet opening and an outlet opening.

It is known from the U.S. Pat. No. 4,206,873 and the Danish PatentApplication No. 5120/79 to brake a flow of liquid by passing ittangentially into a housing which has a substantially circularcross-section and forms a vortex chamber. It is common to these vortexbrakes that it is a prerequisite for the eddy formation and thus thebrake effect that the inlet to the brake housing is tangential to thehousing and also substantially perpendicular to the outlet direction.However, a deviation of up to about 60° from the perpendicular or downto an angle of 30° with the axis is acceptable, provided that the walltoward which the inlet is directed is almost perpendicular to the outletdirection.

Within the liquid flow control field there is an increasing need for amore sophisticated control and a less problematic principle ofincorporation. By more sophisticated control is meant the possibility ofvarying the brake effect of the brake housing within a very greatinterval and of simultaneously maintaining a very large flowcross-section in the control of small amounts. Less problematicprinciple of incorporation is taken to mean one which allows the brakehousing to be inserted in a straight conduit.

The object of the invention is to provide a device of the stated typewhich satisfies the mentioned need.

This object is achieved by an adjustable guide vane in or opposite theinlet opening, said guide vane being so arranged and mounted as to bemovable between an extreme position in which it is positionedsubstantially outside the inlet region, and operative positions in whichit extends more or less across the inlet opening and gives the inflowingliquid a velocity component which forms an angle with the direction tothe outlet opening. Then the movable guide vane enables deflection ofthe inflowing stream of water away from the inlet direction so that, ata certain pressure height at the inlet, the water is caused to follow avortex path through the housing with a consequent brake effect. Thedegree of deflection and thus the pressure head where the eddy formationbegins can be varied by adjustment of the guide vane. This adjustmentcan be made at the installation having regard to the actual flowconditions, but can of course always be corrected when the circumstancesso demand, e.g. in case of changes in the pipe system in which thedevice is incorporated.

When the water is caused to rotate in the housing by a sufficientlygreat pressure head at the inlet, it will be whirled out against thecurved side wall under the action of the centrifugal force and withcontinued inflow be displaced inwardly toward the central axis of thehousing, where the number of revolutions increases because the waterpath per revolution becomes shorter with a decreasing radius. The innerwater particles with the large number of revolutions will tend toentrain the most adjacent outside water particles with the same numberof revolutions; this effect takes place through the entire body of waterout to the periphery and results in a very great overall centrifugalpressure against the curved housing wall and a correspondingly greatbrake effect. Under these circumstances the water leaves the outlet as atubular, thin-walled jet.

In practice, the device of the invention may have the shape of either afrustum of a cone and be arranged as stated in claim 2, or of a flatcylinder and be arranged as stated in claim 9.

Expedient details in the two shapes are defined in claims 3-8 and 10-11,respectively.

The invention will be explained more fully below with reference to thedrawing, in which

FIGS. 1, 2 and 3 show an embodiment of the device of the invention, seenfrom the side, from the top and from the inlet end, respectively,

FIG. 4 is a perspective view of a modified embodiment of the guide vaneand a sector plate on which it is mounted as well as a part of thehousing,

FIG. 5 is a perspective view of a modified embodiment of the inletnozzle and a part of the housing,

FIGS. 6, 7 and 8 show another embodiment of the device of the invention,seen from the inlet end, from the side and from the face opposite theoutlet opening, respectively.

The device shown in FIGS. 1, 2 and 3, which is generally designated by10, has a lying, frusto-conical brake housing 11 with an end wall 12,whose lower portion is formed with an inlet opening 13, and with anoutlet opening 14 in the narrow end. The inlet opening 13 and the outletopening 14 are connected to an inlet spout 15 and an outlet spout 16,respectively, both of which may be equipped with coupling flanges,insertion sleeves and various forms of valves, quantity flow meters andfittings in a generally known manner. A calibration ring 17 is shown inthe outlet spout 16.

The exterior of the end wall 12 mounts stiffeners 18 and a bearingbushing 19, co-axial with the housing, for a through shaft 20. Anadjustment arm or lever 21 movable across a scale plate 22 is secured tothe shaft. Moreover, means (not shown) may be provided for holding thelever 21 in any desired position. The interior end of the shaft 20mounts a substantially sector-shaped plate 23 which is held in closerelationship with the end wall 12 by a flange 27 downwardly in thehousing and whose one corner portion is replaced by a guide vane; theguide vane is generally designated by 24 and consists of two plates 25and 26 inclined inwardly in the housing from the sector plate edges andinter-connected by two adjoining edges. Upon pivoting of the lever 21the sector plate 23 and the guide vane 24 are moved between a positionin which the sector plate closes the inlet opening 13 completely, andone in which the guide vane is entirely disposed outside the inletopening. The extreme positions may be determined by stop means (notshown).

A vent pipe 28 is positioned on top of the brake housing 11. Instead ofsuch a separate vent pipe, a tubular lever may optionally be used withincommunicates with the interior of the housing through a passage in theshaft 20. However, in may cases venting of the housing is not desirableat all, and it may therefore be expedient to manufacture the device withan upwardly closed vent pipe, which can then be opened by drilling of ahole in the top end, when so desired.

In the modified embodiment of the guide vane shown in FIG. 4, the guidevane is formed by a curved plate 29 which results in better flowconditions than the one shown in FIGS. 1-3. The plate 29 may e.g. be inthe form of a portion of a cylinder face whose generatrix is directedobliquely into the housing 11.

The modified embodiment of the inlet spout 15 shown in FIG. 5 has alaterally directed extension at the inlet opening 13, said extensionbeing defined by a curved plate 30 which may e.g. form part of acylinder face with a generatrix which is substantially parallel with thegeneratrix of the guide vane 29.

When the adjustment lever 21 is pivoted to its outermost clockwiseposition in FIGS. 2 and 3, the sector plate 23 blocks the inlet and thusprevents through-flow. When the lever 21 is pivoted to its outermostcounterclockwise position, the guide vane 24 or 29 will be disposedentirely outside the flow profile, with a free flow without brakeeffect. When the lever is placed in its middle position, the guide vanewill be in the brake position, and with a moderate inflow the waterimpinges on the projecting part of the guide vane and turns over to theopposite side of the brake housing, from where it again slides back tothe bottom and leaves through the outlet. In case of an increasedpressure the effect is enhanced so that the water turns along the innerside of the housing before leaving through the outlet, and finally theentire amount of air, apart from an air column up through the centre ofthe brake housing, will be displaced through the outlet to provide fullbrake effect. When the water pressure falls again and declines to aboutthe middle of the brake housing, the rotation becomes unstable, and airfrom the outlet end will return to the top of the housing and break therotation so that the brake effect ceases and the flow increases abruptlyand briefly, which causes any sedimented substances to be whirled upinto the flow. At other intermediate guide vane positions the mode ofoperation is in principle the same, but the brake effect and thus theflow are different. The greater the opening, the smaller the brakeeffect, and the smaller the opening, the greater the brake effect. Thecharacteristic of the discharge dependence upon the pressure head tendstoward constant discharge at an increasing pressure because ofincreasing brake effect, but declining discharge at a declining pressureto the point where air penetrates and breaks the brake effect.

The embodiment of the device of the invention shown in FIGS. 6, 7 and 8,which is generally designated by 30, has a brake housing 31substantially formed as a flat cylinder and with a plane end wall 32 anda low, frusto-conical end wall 33, whose centre is provided with anoutlet opening 34 connected to an outlet spout 35. In the substantiallycylindrical side wall the housing has a rectangular inlet opening 36which is connected to an inlet spout 37 shown as equipped with acoupling flange 38. The three sides of the inlet spout are plane; butthe fourth side 39 has the shape of a cylinder face with a cross-sectionof a circular arc and with an axis which is parallel with the axis ofthe brake housing 31.

A bearing bushing 40 for a shaft 41 is secured to the plane end wall 32of the housing and co-axially with the curved wall 39 of the inletspout; the shaft 41 extends through the end wall and its outer endmounts an adjustment lever 42 which is movable across a scale plate 43shaped as a circular arc. A guide vane 44 in the shape of a cylindersegment co-axial with the shaft 41 is mounted on the interior end of theshaft 41 by means of an ear 45 coplanar with one end face. A similar earon the other end face of the guide vane 44 has a short centering pin 46,which is co-axial with the shaft 41 and extends through a hole in theopposite side of the inlet spout 37. Pivoting of the adjustment lever 42between the extreme clockwise and counterclockwise positions in FIG. 8,respectively, causes the guide vane 44 to be rotated between a positionin which it closes the inlet opening 36 completely, and a position inwhich its plane inner side is parallel with the opposite side wall ofthe inlet spout 37 and thus allows free flow through the inlet spout.

In the shown embodiment the brake housing 31 has two additional planeside walls 47 extending from their respective sides of the inlet spoutto the substantially cylindrical side wall of the housing tangentiallythereto. Moreover, the brake housing may, as shown, be equipped with anoverflow or vent pipe 48.

When the device 30 is in a horizontal position and the adjustment lever42 is in its middle position in FIG. 8 (as illustrated), the guide vane44 is in the brake position, and water will be deflected at the inletalong the substantially cylindrical side wall of the brake housing whereit continues all the way round to the inlet. Due to continued in-flow,it will be forced closer to the outlet opening, and this effectcontinues until the brake housing is almost filled with water, and thewater leaves the outlet opening as a thin-walled pipe which spreads as afan owing to the centrifugal force caused by the rotation. In the centreof the brake housing there will be an air column which impinges on theplane wall 32 opposite the outlet opening. This effect gets morepronounced with an increasing degree of closure.

When the device 30 is in a vertical position and the adjustment lever 42is in its middle position, the guide vane 44 is in the brake position,and the water runs up into the brake housing along the substantiallyclindrical brake housing side wall from where it falls back over itselfand fills the lower part up to the outlet opening and is discharged fromthe outlet opening. In case of a moderate feed, inflow and dischargewill be balanced at a constant water level in the brake housing.Increasing inflow rates cause the water to rise in the side of the brakehousing where it is guided upwards along the curved wall. The water thenassumes a position inclined toward the outlet opening, which iscompletely filled with water at this moment, and in its fall toward tothe outlet opening it entrains air bubbles out through the outlet untilthe whole amount of air has been displaced and full brake effect hasbeen obtained. The brake effect increases with increasing closure of theinlet cross-section with the guide vane 44. When the pressure and thusthe inlet rate decline and the water level, exteriorly, has reachedsomewhat down on the brake housing, the rotation become unstable, andair will penetrate from the discharge side and break the brake effect.Provided with a vent pipe 48, the device enables easier displacement andrepenetration of air with the same characteristic at an increasing and afalling pressure. Without a vent pipe the characteristic of thedischarge dependence upon the pressure head tends towards a constantdischarge at an increasing pressure because of enhanced brake effect anddecreasing discharge at a falling pressure until the point where airagain forces its way into the brake housing, and the discharge isincreased abruptly and briefly.

The details of the shown and described structures can be modified inmany ways within the scope of the invention. This applies to e.g. boththe arrangement and the mounting of the guide vane and its adjustmentmeans, which may optionally be designed to be controlled automatically,e.g. by a float.

I claim:
 1. A device for controlling the flow of a liquid in a pipesystem, comprising:a housing having a curved side wall to form a vortexchamber therein, said housing having an inlet opening and an outletopening oriented to allow free, unobstructed and substantially linearflow of said liquid through said housing from said inlet opening to saidoutlet opening in the absence of an angular velocity component in aninflowing liquid toward the housing side wall, an adjustable guide vanemounted within said housing and adjacent said inlet opening, said guidevane being movable between the first position in which it is positionedsubstantially away from said inlet opening so as to impart no angularvelocity component to the inflowing liquid toward such side wall, andoperative positions in which it extends at least partially across saidinlet opening to give said inflowing liquid controlled amounts of avelocity component having a direction which forms an angle with thedirection of the inflowing liquid to move said inflowing liquid to saidside wall to create a vortex flow of liquid in said chamber whichcreates a braking effect.
 2. A device according to claim 1 wherein saidhousing side wall has the shape of a frustum of a cone with the outletopening, connected to an outlet spout, in the narrow end of saidfrustum,and wherein said inlet opening, connected to an inlet spout, isdisposed in a lower part of the wide end face so that said inlet spoutand outlet spout are substantially horizontal and co-axial with eachother.
 3. A device according to claim 2, wherein said inlet spout atsaid inlet opening of said housing is formed with a lateral extensiondefined by a curved wall which is substantially parallel with said guidevane.
 4. A device according to claim 2 wherein said inlet opening issubstantially circular,and wherein said guide vane is curved andarranged along an edge portion of a planar supporting plate which ispivotally placed on the inner side of and in close relationship withsaid wide end face, said edge portion substantially conforming with andbeing positioned along a part of the inlet opening circumference in oneoperative position of said guide vane.
 5. A device according to claim 4wherein said wide end face is circular and perpendicular to the axis ofsaid frustoconcical housing,and wherein said guide vane supporting plateis substantially sector-shaped and is rotatable about the axis of saidhousing and has a size at the wide end face circumference sufficient tocover said inlet opening completely in an operative position of saidguide vane.
 6. A device according to claim 3, comprising:an inclinedplate extending obliquely from a part of said guide vane inwardly towardsaid guide vane supporting plate.
 7. A device according to claim 4,wherein said guide vane supporting plate is firmly connected to a leverwhich is mounted on the exterior of said housing and is movable across ascale to rotate said guide vane supporting plate.
 8. A device accordingto claim 7, wherein said lever is hollow and forms a vent pipe.
 9. Adevice for controlling the flow of a liquid in a pipe system,comprising:a housing substantially in the shape of a flat cylinderhaving end walls with an outer opening in one end wall and an inletopening in the cylindrical housing wall, an inlet spout connected tosaid inlet opening to normally direct the flow of liquid into saidhousing substantially radially to the center of said cylindricalhousing, a guide vane mounted in said inlet spout, means for moving saidguide vane between a first position in which it is positionedsubstantially away from said inlet opening to allow free, unobstructedand substantially linear flow of an inflowing liquid substantiallyradially into the housing, and operative positions in which it extendsat least partially and obliquely across said inlet opening to directsaid inflowing liquid away from said radial direction to impart to it acontrolled velocity component having a direction which forms an anglewith the radial direction of inflow from said inlet opening so as todirect the inflowing liquid to the cylindrical wall to give a brakingeffect to the liquid as it travels from the inlet to the outlet.
 10. Adevice according to claim 9 wherein said inlet opening and correspondingcross-section of said inlet spout are rectangular,and wherein said guidevane is in the shape of a cylinder segment having a plane side in saidfirst position disposed in parallel with an opposite side wall of saidinlet spout and defines, in combination with said side wall and twowalls of said inlet spout perpendicular thereto, a cross-sectioncorresponding to that of said inlet opening.
 11. A device according toclaim 9, wherein said guide vane, through its pivot, is firmly connectedto a lever which is mounted on the exterior of said housing and ismovable across a scale.
 12. A device according to claim 9 wherein saidradial inlet spout has a curved side wall along which an outer edge ofsaid guide vane moves upon rotation of said guide vane.